exponent

1 a person who actively supports or favors a cause exponents of space exploration earnestly called for more missions to the outer reaches of the solar system Synonyms advocate, advocator, apostle, backer, booster, champion, expounder, espouser, friend, gospeler (or gospeller), herald, hierophant, high priest, paladin, promoter, proponent, protagonist, supporter, true believer, tub-thumper, white knight Related Words loyalist, partisan (also partizan), stalwart; adherent, cohort, disciple, follower; interpreter; applauder, cheerleader, encourager, fellow traveler Near Antonyms enemy, foe, rival; belittler, critic, faultfinder Antonyms adversary, antagonist, opponent

2 one who brings an art or science to full realization has long reigned as the nation's leading exponent of modern dance Synonyms expounder, guru, high priest, interpreter, practitioner Related Words dean, doyen, grand old man; ideologue (also idealogue), philosopher, theorist; advocate, apostle, backer, booster, champion, promoter, proponent, supporter